Oxygenates, synthesis process variations

The synthesis of furanones (y-lactones) from alkynes and carbon monoxide consititutes a unique variation of the [2 + 2 + 2] pattern. The ring incorporates both carbons from the C=carbon from one CO, and both carbon and oxygen from the other CO. The process is therefcMe a 2 + 2 -i-1 cycloaddition of the form [2TTfw + Zno-o 2ncol- The formal result of such a cycloaddition is a carbene at position 4, the carbon atom of the irco participant (equation 12). 

Oxygen-containing Heterocycles Three-membered Rings. - The addition of oxygen to double bonds remains the most common method for epoxide synthesis, and several new variations on that theme have appeared this year. Thus, alkenes are converted into epoxides using a solution of elemental fluorine in an acetonitrile/water mixture with complete retention of olefin stereochemistry.1 Prat and Lett have re-examined the use of tungstic acid catalysed epoxidation in an attempt to define the scope and synthetic utility of the process. They have shown that reactivity increases with the nucleophilicity of the double bond and... 

The Synol and isosynthesis processes, as well as the Oxyl and iron nitride variations of the Fischer-Tropsch synthesis, were developed to produce special products from synthesis gas. All but the isosynthesis are designed to produce high yields of oxygenated materials. The isosynthesis yields highly branched aliphatic hydrocarbons and aromatics. While none of these processes has been used commercially, they could be of interest at some future time. 

The lability of the Cul-04 bond, responsible for the oxygen nonstoichiometry, also allows ordering processes in the chains. Indeed, it was found very soon that depends not only on the occupancy of the chains but also on the ordering imposed by the thermal history (sect. 3.2.1.5), pressure (sect, 5.4), chemical history (sect. 3.2.2.5) and the general conditions of synthesis of the samples. Thus, the appreciable dependence of structure on oxygen content varies considerably with synthesis conditions. With a lot of fantasy and mostly no adherence to equilibrium thermodynamics many variations of the synthesis conditions have been tried. 

Two major versions of the MTG process currently exist. The first, as exemplified by the New Zealand GTG configuration, is a fixed-bed process the second is a fluidized-bed process. A third process concept, the Topsoe TIGAS [40], integrates methanol synthesis with MTG. This variation uses a multifunctional catalyst for producing a mixed oxygenate feed (including methanol) from synthesis gas and was tested... 

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